1. Field of Invention
The present invention relates to an array structure for an active device of optically self-compensated birefringence liquid crystal display. More particularly, the present invention relates to an array structure of an active device, capable of causing the liquid crystal layer in an optically self-compensated birefringence type to fast twist the LC molecules from the splay state and then be transited into the bend sate.
2. Description of Related Art
The multi-media sociality has been greatly developed. This is because of the great development on the semiconductor fabrication or the human-device displaying apparatus. With respect to the displaying device, the cathode ray tube (CRT) in recent years has constantly occupied most of the market due to its advantages of displaying quality and the economic consideration. However, for the environment that a person can operate multiple terminals/display-devices on a desk, or from the environment protection point of view, if the issue of power consumption is under consideration, it can be foreseen that the CRT has its issues without solution. The CRT cannot have the properties, such as being light, thin, short, small or low power consumption. Therefore, the thin film transistor liquid crystal display (TFT LCD), with the great properties of high image quality, improvement of space using efficiency, low power consumption, no irradiation, has gradually been the main stream in the market.
The liquid crystal display has been categorized into several types, according to the liquid crystal type, driving method, and light source implementation. Wherein, the OCB (Optically self-Compensated Birefringence ) LCD has fast responding speed, and can provide the smooth images in change, when the computer displays the continuous images in prompt change for play the moving image or the movie. The OCB also stands for Optically Compensated Bend, and Optically Compensated Birefringence respectively. It is very suitable for application on the high level LCD. However, the OCB LCD has to let the liquid crystal molecules to be transited from the splay state to the bend state, and then it can enter the standby state for providing the function of fast responding speed.
FIG. 1A is a drawing, schematically illustrating the liquid crystal molecules for the OCB LCD. FIG. 1B is a drawing, schematically illustrating the OCB liquid crystal molecules at the bend state. In FIG. 1A and FIG. 1B, the OCB liquid crystal molecules 100 are disposed between an upper substrate 110 and a lower substrate 120. Wherein, the upper substrate 110 and the lower substrate 120 respectively have alignment layers with an alignment direction in parallel. When the OCB liquid crystal molecules 100 are not applied with the external electric field, the liquid crystal molecules are aligned in a splay state. When the OCB LCD intends to enter the standby state, it is necessary to apply an electric field, perpendicular to the upper substrate 110, onto the OCB liquid crystal molecules 100, so as to gradually transit to the bend state. For the conventional OCB LCD, it needs a few minutes to perform this transition, in order to be properly driven. This means that it needs a certain time for warm up before entering the standby state. This is very harmful for the LCD, which should have the function to be ready while being turned on. Therefore, it is necessary to have the fast transition for the OCB LCD, so as to be easily accepted by the user.
In the conventional skill, one way to achieve the fast transition is done by a specific driving method. Another way is that a specific pixel design is taken, so as to cause a portion of the liquid crystal molecules to be in a specific alignment, and thereby accelerate the transition duration from the splay state to the bend state.